Physiology and pathophysiology of the β 3 -adrenergic receptor.

The β3 -adrenergic receptor (β3 -AR) is an important regulator of various physiological functions, such as thermogenesis in brown adipose tissue, lipolysis in white adipose tissue, negative inotropic effect in cardiomyocyte, and relaxation in blood vessel. The activation of β3 -AR by its agonists is shown to have metabolic (antiobesity and antidiabetic) and cardiovascular effects in animal models, highlighting β3 -AR as a potential therapeutic target in the treatment of several human diseases. Moreover, a substantial number of studies performed on different populations have identified some β3 -AR polymorphic variants associated with obesity, diabetes, cardiovascular diseases, and other disorders. The clinical phenotypes and functional characteristics of these variants provide insights into potential pathophysiological roles of β3 -AR in the development of these diseases.